Improvement in middlings-separators



G. T. SMITH.

. MIDDLINGS-SEPARATOR.

No.187,923. Patented Feb. 27,1877.

NFERS, FHOT0 LJTHOGRAFHEIL WASHINGTON. D C4 UNITED STA'rns PATENT @rr-Ion GEORGE T. SMITH, OF WASHINGTON, DISTRICT OF COLUMBIA.

IMPROVEMENT IN MlDDLINGS-SEPARATORS.

Specification forming part of Letters Patent N o. 187,923, dated February 27, 1877 application led December :18, 1876.

To all whom it may concern:

Be it known that I, GEORGE T. SMITH, of Washington, in the District of Columbia, miller, have invented certain new and useful Improvements in Middlings-Puriers; and l do hereby declare that the following isa ful1,clear, and exact description thereof, which will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

Middlings, when delivered to a purier, consist, ordinarily, of a mixture of pure' and fine iiour, granules of the ilour-producin g portion of the wheat in various grades or sizes of granulation, and bran or other refuse material, the grains or particles of which correspond substantially in size to those of the our and hour-producing material, this range or gradation usually extending from -a size which will pass through the mesh of a No. l0 bolting-cloth, or even finer, to such as will hardly pass through a No. 2 or a No. 3 cloth, or even coarser.

I have found that, in order to 'purify middlings thoroughly and economically, it is frequently necessary to pass them over a succession of machines, or else over the same machine inore than once, and that it is also necessary to employ a series of bolting-cloths upon each shaker, grading the cloths from ne at the head or receiving end of the shaker to coarser ones toward the tail or discharging end of the bolt or shaker, using graded aircurrents through the bolting-cloth, produced by dividing the air-chamber into sections by means of transverse partitions, each section being provided with a valve or damper, where by a light draft may be used upon or through the line cloth through which the fine middlingsare passing, a heavier or stronger draft through the coarser cloth, and so on.

I have also found that, in order to separate the fine refuse 'from the finest middlings b y the combined operation of the air-current and the reciprocating movement of the boltingclot-h, it is important that more or less of the coarse `material should be intimately incorporated with the nest, one reason why this mixture of grades is essential being the fact that the very fine our or middlings will not pass readily through the meshes of the tine cloth unless it is thus mixed with the coarser as it lies in a thin sheet or layer upon said cloth.

Thus it will be' seen that a machine which shall meet the above requirements must manipulate or treat the middlings in substantially the following order or sequence: It must receive them while the different grades or sizes of particles or 'granules are intimately mixed or incorporated with each other, and, by means of a graded bolting-cloth, separate the mass into a number of different sizes of granules, treating each grain with or by an air-current, the strength of which is regulated according to the number of the cloth and the neness of the material passing over it, and must then be restored, as nearly as possible, to its original condition, so far as relates to a thorough incorporation of the coarse and fine particles, whereby the middlings are prepared for a second purication.

The invention for which protection is sought in this patent consists of certain features of construction and combination, as will be fully understood from the following description.

Figure l is a plan or top view of the machine. Fig. 2 is a vertical transverse section, and Fig. 3 is a vertical longitudinal section.

A represents a hopper, into which the middlings to be treated are delivered from an elevater, or by any other means. The iniddlings are fed by the roller B to the bolt or shaker b, the amount of feed heilig regulated by a slide, c. The shaker is arranged in a chamber, through which an air-current is made to pass in an upward direction by means of a fan, D, the air entering through suitable openings C in the side of the bolt-chest. The bolt or shaker is suspended from the frame-work by means of pivoted links lr r, and has a reciprocating motion imparted to it by the eccentric R on shaft R, and the inclosing-box I.

H H are brushes attached to and carried by endless belts h, the brushes being carried, during their contact with the bolt, upon ways k k, and, by preference, I make the frame- Work and ways which support the brushes adjustable by means ot' set-screws k', (see Fig. 2,) so that l can keep the brushes always in contact with the bolt.

b1 b1 are supporting-ribs attached to and forming a part ofthe bolt or shaker b. These ribs are arranged longitudinally of the shaker, their lower edges being in the saine plane with the lower edge of the sides ofthe shaker-t'rame, the bolting-cloth b2 heilig secured both to the shaker and to the supportingribs bl b1.

As it is very desirable that the layer or sheet of middlings upon the bolting cloth should be of as nearly as possible an equal depth across the entire width oi' the shaker, in order that the air-currents shall act with uniformity upon the iniddlings; and as it is impracticable to have a series of these ribs upon the under side of the cloth, on account of their being in the way of the brushes, it will be seen that they (the ribs) upon the upper side of the cloth perform an important function in keeping the cloth in a plane, by preventing it from sagging. This feature of construction also enables thc operator to adjust the brushes to act upon the entire width 0f the cloth uniformly.

J is a spiral or worm conveyer, arranged in the conveyer-box J. The middlings, after passing through the shaker, are conducted to the conveyer-box by means ot' gather-boards J2. (See Fig. 2.)

jj1 y""j3 are cut-oi`` slides or gates in the bottom of the conveyer-box J1.

The space within the Walls ot the machine and above the shaker is divided, by vertical transverse partitions ef, into three aircham bers, E F G.

Dis an exhaust-fan, connected by means of air-trunks E F G with the airchambers.

m ml m2 are shelves arranged in zigzag form within each ot' the air-chambers, the air-currents passing around these shelves, as indicated by the arrows Jr. (See Fig. 3.)

n n n are valves arranged upon the upper side of the lower shelf in each air-chamber, and operated by means of a rod, n', and it is apparent that by drawing these valves rearward a narrow throat can be formed between the rear edge ot' each valve and the opposing wall or partition, and that thus the strength ofthe air-draft may be rendered nearly uniform across the entire width ot the shaker in each air-chamber.

The iniddlings are fed from the hopper A to the shaker by thc feed-roller B, and as they pass over the iine cloth at the receiving end of the shaker they are thoroughly agitated by the reciprocating motion; and, through the combined eiiect of the agitation and the upwardly-ascentling air-current, more orless of the refuse is brought to the surface, the finer and lighter parts being taken up by the air, the finest of the niiddlngs falling through the bolt-cloth. Another portion of the refuse, which is too heavy to be carried away by an air-current of such strength as can be advantageously used in the air-chamber E, is iioated along until it reaches the second air-chamber F. In this chambera stronger draft can be safely used, (the finest of the middlings having been bolted out,) which will take out a part of the still heavier refuse, and will oat another portion still farther toward the tail, where it can be carried away, or be floated over the tail of the shaker.

I have found by experience that it is very difficult, if not impossible, sui'cieutly to purify middlings by running them once through a machine, modified, it is true, by their condition. Hence, through the cut-oi slides, I remove such of the tine middlings as are sufh'ciently clean, if there be any, and then, by means of the conveyer J, which moves the middlings material in the direction of the arrow y, with a peculiar rotary motion, I thoroughly incorporate and intermix the coarse middlings from the tail end of the shaker with the fine ones at or near the head of the shaker, thus putting them in the best possible condition for a subsequent purifica.- tion.

Another feature of construction which is valuable in the machine is this: By locating the air-chambers E F G, the air-trunks E l1" G', and fan at the upper part of the machine, l accomplish four desirable results First, I economize room, as in nearly all mills there is space enough between iioors to put a machine thus constructed, and this arrangement saves the space which would be occupied by the trunks and fans if they were located at the side or end of the machine; secondly, the machine is more readily gotten at with the air-trunks on top; thirdly, the air-currents are more uniform in their action upon the entire width of the cloth when the sectional chambers are above the shaker; and, fourthly, the brushes have an unobstructed space in which to travel when the partitions forming the air-chambers are above the shaker.

I do not claim in this patent, which is a division of my original application, anything except the specific invention set forth and described and claimed herein; but

What l do claim is,-

1. 'lhe combination, in a doar-dressing machine, of a reciprocating shaker, having holting-cloth of different degrees of tineness, an air-chamber arranged above the shaker, and divided into sections by transverse partitions, and a conveyer below the shaker, whereby the middlings may be divided into grades of tineness, and subjected to air-currents of different degrees of strength, and afterward intimately remixed for a second purication, substantially as set forth.

2. The combination, in a Hour-dressing machine, of a reciprocating shaker clothed my own I ax my signature in presence of two witnesses.

GEORGE 'I'. SMITH.

Witnesses:

ALFRED HosKIN, 0f the City of Toronto, Barrister-@Lam ALBERT OGDEN, City of Toronto, Student-at-Law. 

